Add A Block Which is Simular to the Openblocks /DEV/NULL
The /CRON/NULL is used to discard all of a single item type when they are picked up.
It has a single inventory slot, which can be accessed through sneak-using it when not targeting anything.
The item inserted is the "filter" item.
Once the stack in that slot is full, all exact items will be immediately discarded on pick-up.
If the /CRON/NULL has a block in its slot, it can be used to place the block.
